Wireless communications systems are widely deployed to provide various types of communication content such as voice, video, packet data, messaging, broadcast, and so on. These systems may be multiple-access systems capable of supporting communication with multiple users by sharing the available system resources (e.g., time, frequency, and power). A wireless network, for example a Wireless Local Area Network (WLAN), such as a Wi-Fi network (IEEE 802.11) may include an AP that may communicate with one or more STAs (e.g., mobile devices or client devices). The AP may be coupled to a network, such as the Internet, and enable a mobile device to communicate via the network (and/or communicate with other devices coupled to the AP).
As wireless technologies improve and become more wide spread, the demand for continuous connectivity for STAs is increasing. Technologies, for example implementing IEEE 802.11 standards (e.g., WLANs such as Wi-Fi and Wi-Fi Direct or Peer to Peer (P2P) networks) have been used to address this demand. However, with higher connectivity rates, power or battery consumption of WLAN configured STAs greatly increases. To mitigate this problem, a WLAN STA may sleep or go idle for a time, then wake up at regular intervals to receive a beacon from an AP, which may further indicate to the STA whether to stay awake for pending data transmission from the AP. For example, the beacon may include an indication of whether the AP has one or more packets to transmit to the STA, such as in a traffic indication map (TIM) information element (IE). As beacon size increases, so does the amount of time during which the STA remains awake to receive the beacon. The increase in wakeup time may equate to increased power consumption by the STA, resulting in decreased battery life and user experience.
Additionally, the time during which the STA remains awake to receive a beacon may be affected by congested wireless environments. Congested environments may cause beacon drift, meaning that the AP's target beacon transmission time (TBTT) may not be constant (e.g., due to carrier sense multiple access with collision avoidance (CSMA/CA) techniques implemented in WLANs). Beacon drift may further cause the STA to wake up either early or late to receive the beacon, resulting in a longer wakeup time to receive the beacon and increased power consumption by the STA or a failure to receive the beacon.